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PICO MACOM INC.  12500 Foothill Blvd.  •  Lakeview Terrace, CA 91342  •  (818) 897-0028 •  (800) 421-6511 •  FAX (818) 834-7197

3

Section 4

D E S C R I P T I O N S

A N T E N N A    S E L E C T I O N

Pre-Amp

MPA-25

Broadband

Single Channel 

VHF

MX-7

0R

LOW 

VHF

DSV-3

DSV-4

HIGH 

HLSJ

20 dBmv to 
Headend

10 dBmv

UV SJ

UHF

MX-4U

19 dBmv

DC-20

Test

-1 dBmv

18 dBmv

11 dBmv

12 dBmv

DC-20

Test

UHF

DSU-3

UVSJ

20 dBmv to 
Headend

19 dBmv

-1 dBmv

18 dBmv

17 dBmv

12 dBmv

9 dBmv

10 dBmv

12 dBmv

The  proper  reception  of  Local
Off-Air 

Television 

Signals

(UHF-VHF) is essential to a quality
Private Cable system.  The use of a
commercial quality off-air antenna
is  a  must  for  optimum  television
reception.  Since every location has
different needs and problems, a site
survey should be completed before
starting the system.  There are three
methods of off-air reception; Broad-
band, Single Channel Yagi or a com-
bination of both.  The method to use
will  depend  on  the  direction  the
signals come from and the strength
of the  signals.  A good quality field
strength meter is a must for measur-
ing signals.

Broadband Antennas

These are used in areas with moderate
to strong signal levels and when the
signals  are  coming  from  the  same
general direction.  A mast mounted
broadband, low noise pre-amplifier
is recommended to boost the input
levels to over 20 dBmv. The incom-
ing  headend  signal  is  divided  into
the  VHF  and  UHF  bands  using  a
UVSJ  separator.  A  DC-20  (direc-
tional coupler) is inserted for use as
a 20 dB down test point.   The UHF
signals are then split with a DSU- *
series  splitter  and  inserted  into  a
converter or channel processor.  The
VHF signals are band separated once
again using a  HLSJ hi/low separa-
tor.  The low and high band signals
are  then  split  using  DSV-*  high
isolation splitters. Each splitter out
is routed to the proper headend com-
ponent.
* The number of ports is determined
by the number of channels.

Another option on VHF signals is to
use a MX-7 or MX-4V.  The MX-7
& MX-4V are frequency selective
splitters  for  up  to  7  non-adjacent

10 foot dish.   In some areas where
the signals are very weak (outside
60  miles  from  the  transmitter)  a
single  channel  pre-amplifier  must
also be used to bring the signal to
usable  levels.    Because  these  are
made to a specific channel they can
be entered directly into the headend
strip amplifier converter or proces-
sor input.  High gain UHF antennas
are designed to cover blocks of chan-
nels  such  as  14-26,  26-38,  38-50,
50,62, 62-74 etc.

Combination Broadband & Single

Channel Yagis

Using a combination of antennas is
common  in  areas  that  have  many
variable signal levels coming from
different  directions.    A  good  ex-
ample is sites located between Los
Angeles, and San Diego.  Los An-
geles  has  2,4,5,7,8,11,13,28  com-
ing from the North, San Diego has
6,8,10,39 from the South.

The signals received off of broad-
band antenna will vary by as much
as 15 dB form channel to channel.
Signals received off an antenna are
never adjacent.  A channel 2 would
not  be  located  in  the  same  geo-
graphic  location  as  a  channel  3
(channels  4  and  5,  and  channels  6
and 7 are adjacent in number only).
Part 73.606 of the “Code of Federal
Regulations” can be used to locate
the transmitter locations in the vi-
cinity of your headend.  The Soci-
ety of Cable Engineers (SCTE) also
sells a paperback book of mapped
locations of each FCC licensed VHF
transmitter.  The cost of the manual
is  less  than  $25  and  is  well  worth
the price.

VHF  channels.  Built  in  attenua-
tors  help  adjust  signal  levels
evenly.

Single Channel Yagi*

These  are  used  when  the  signals
are  coming  from  opposite  direc-
tions  and  at  lower  signal  levels.
Single channel VHF Yagis are cut
to a specific channel enabling the
antenna to have much higher gain
than a broadband antenna.

*Note  that  the  lower  the  VHF
frequency the larger the antenna.

It is analogous to satellite systems
using a 16 foot dish instead of an

All manuals and user guides at all-guides.com

Summary of Contents for 72H

Page 1: ...Lakeview Terrace CA 91342 818 897 0028 800 421 6511 FAX 818 834 7197 Installation And Operation Manual SINGLE CHANNEL AMPLIFIERS LBS FMS MBS HBS UBS 72L 72M 72H 72S All manuals and user guides at all...

Page 2: ...uct on an unstable cart stand tripod bracket or table The product may fall causing serious injury to a child or adult and serious damage to the appliance 9 Ventilation This video product should never...

Page 3: ...the operatinginstruction Adjustonlythosecontrolsthatarecovered bytheoperatinginstructions Animproperadjustmentmayresult in damage and will often require extensive work by a qualified technician to re...

Page 4: ...by the number of channels Another option on VHF signals is to use a MX 7 or MX 4V The MX 7 MX 4V are frequency selective splitters for up to 7 non adjacent 10 foot dish In some areas where the signals...

Page 5: ...st way to explain AGC is with an example Assume a strip amplifier has a maximum gain of 54 dB and the output is set to 55 dBmv The input to the amplifier is initially 10 dBmv Only 45 dB 55dBmv 10dBmv...

Page 6: ...MHz 30 dB F center 9 MHz 45 dB UBS 3 Channels 50 dB 6 Channels 65 dB FMS Switchable Wide Channel 5 40 dB Narrow Channel 6 20 dB Noise Figure LBS MBS HBS 72L 72M 72M 6 dB 72S 7 dB UBS 9 dB Controls AGC...

Page 7: ...The signal originating from a broadband or yagiantennaisconnectedatthisFconnector Refer to page 3 for information on antenna selection and proper input levels 8 OUT The filter amplified signal is dir...

Page 8: ...amplifier modulator and processor outputs The PHC 12 consists of two rows of direc tional couplers combined by a hybrid splitter The directional coupler combining provides highisolation 40dB betweenth...

Page 9: ...nnel The Pico Macom single channel amplifiers can be alignedtootherchannelswithinthefrequencyband The input and output filter components within the Test Equipment Sweep Generator System Wavetek 1076 1...

Page 10: ...the Thru and Out connectors Adjust the bandstop thru filter C4 and C5 for a response similar to the figure to the right 9 Connect a TV signal generator to the input and a spectrum analyzer to the str...

Page 11: ...Authorization RA number which will be used to track your product Be prepared to provide 1 The model number and channel number of the product 2 The date of purchase 3 A specific identification of the p...

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